Cowl fastener



Patented June 30, 1936 uNir-Eo. STATES PAT ENT F'Fjl CE COWL FAS TENER. La Vergne Cook, Dayton, Ohio I Application August 17 1934, Serial No. 740,281 3 Claims. (Cl. 292 -207) (Grantedunder the act of March 3, 1883,,as amended April 30, 1928; 37-0 757 The invention described herein. may be manufactured and used by or for the, Government for governmental. purposes, without the payment to me of any royalty thereon.

This inventionrelates generally to cowling; for inclosing airplane engines and other. parts for reducing. parasitic .resistance, and more particularly to. latch means for fastening the, cowl to its support.

10. An object of the invention-is to provide an improvedcowl latch capable of being manually operated in a convenient and facile manner to fasten and uniasten thecowling with respect to its support and which, in process of fasteningthe =cowling, tends to draw the cowling tightly against the support in a firm-and secure manner.

Anotherobject of the invention-is to provide a cowl-latchhaving auxiliary means operable, in the fastening position of. the latch, to prevent the latter from being loosened or unfastened by shock,-ja-rs or vibrations.

A specific embodimentv of the invention, whereby the above and other objects areattained, is herein set forth and described in detail; with reference to the accompanying drawing; where- Figure 1 isa-view inelevationofa cowlfrag ment and. its support with the invention applied thereto;

Figure 2- is avertical, longitudinal sectional view on line 2-.-2 of Figure 1;

Figure 3--is a horizontal cross sectional view on line 3- -3. of Figure 1,; Figure 4 is a view similar to Figure 1, but with 'the latch;-.knob;removed and the auxiliary latchholding means shown in operative position.

Figure 5 is a rear View, in perspective, of fragments of a cowl and its support with the latch lever and detent element disconnected.

In the drawing, the cowling I and the cowl support 3 are shown in relative engagement with their adjacent edges overlapping, the edge of the cowling being on the exterior side of the support edge. The lever or latch bar 5 of the cowl fastener is disposed against the inner side of the cowl and has a lower hooked end 1 adapted in the process of fastening the cowl to the support, to hook over a block 9 on the inner side of the support. The latch bar is pivotally attached to the cowling by means of a bolt H, spacer I3, nut I5 and cotter I1. The block 9 is secured to the support by suitable means, such as rivets I9, in vertical alignment with the pivot-bolt I I and has the end to the right of the bolt in Figure 1 curved, as at 2|, on an arc concentric with the pivot II.

The block is also. tapered with the, thin edge at, the curved end,-as will be apparent from Figures 1 and 3. 4

The latch bar is swung about its pivot by means of a .hand- -knob' 23iarranged exteriorly of the. cowling andconnecting with the upper end pore tion of the latch. bar through an arcuate slot 25, in cowling I concentricwith pivot II. The slotis positioned to .the. le ft of the bolt with its upper terminal vertically above. and in line with the pivot, as shown in severalof the yiews. When the knob-end of the latch bar. is positioned at the lower extremity of the slot 25, the hooked end I is clear of the block 9 and the Cowling is unfastened withrespect. tothe support3. To fas ten the cowling, the latch-baris pushed back along the slot to the-upper terminal of the latter, causingthe hookedend'l to be engaged overthe block 9.

In the operation of the latch,.the hooked end of thelattenmoves.on and'off the block from; the thin curved end, of the latter andbyreason of the taper'of the block, the cowlingis'drawn, tightly against the, support as the hookedendof thelatchbaris forced, more and,more toward. the thicker end of -the block. This insuresfaf tight fit between the cowling and. the cowlingsupport and at-thesame time, provides [for securely fastening one to the 'other. V v

To, retain the latch bar in fastening position, auxiliarym-eans} are provided whichinclude a. studllarranged in a.slot- 29 -exte nding longie tudinally of the upperend of the latch bar and radially of, the pivot; II. This .studI extends r u h tea er}. 29 "twee q h e o e latch bar, with its outer end secured to or made integral with the hand-knob 23 and having an oval or elliptical shaped portion 3I designed to lie within and move along the cowl slot 25 with its major axis in the plane of the slot and perpendicular to the top and bottom edges of the slot. The head or knob 23 of the stud is normally thrust against the outer side of the cowling by the tension of a spring 33 encircling the shank of the stud between two thrust washers 35 and 31 the former seating against the inner face of the latch bar and the latter seating against a nut 39 adjustable on the shank for varying the spring tension and held against displacement from the stud by means of a cotter 4|. A look slot 43 is provided in the cowling below the upper terminal of the arcuate slot 25 to receive the elliptical shaped portion 3| of the stud when the latter is at the bottom of the latch bar slot 29. This lock slot is of the same shape as the stud portion 3| but is disposed with its major axes at right angles with the longitudinal center line of the latch bar. Communication between the arcuate slot 25 and the lock slot 43 is afiorded through a connecting slot 45 which is of a width to permit passage of the stud therethrough only when the elliptical-shaped portion of the stud has its minor axis broadside of the connecting slot.

The auxiliary latch-bar lock is operated subsequently to the shifting of the latch bar from the off condition indicated by the dotted line structure of Figure 1 to the on position indicated in full lines. The stud 21, in the on condition of the latch mechanism, is normally at the upper end of the latch bar slot 29, but in looking the latch bar in its on position the stud is moved downwardly to the bottom of slot 29; causing the elliptical shaped portion 3| of the stud to pass from the arcuate slot 25 to the lock slot 43 through the connecting slot 45. The stud is then pulled outwardly by the knob 23 and against the tension of spring 33 until the stud portion 3| is clear of the lock slot 43. The knob is then given a 90 degree turn to properly position the stud portion 3| with respect to the lock slot 43 and then released upon the stud portion as drawn into the lock slot, as shown in Figure 4, by the tension of the spring 33. The latch bar is thus held in its on condition firmly and securely against any movement about its pivot, and can be shifted to off position only when the stud portion 3| is disengaged from the lock slot and shifted upwardly to the arcuate slot 25.

As will be noted from the foregoing, the arrangement and operation of the latch mechanism is simple and reliable. The cowling shelters and protects the mechanism, by reason of the placement of the latter interiorly of'the cowling and the exposed knob provides convenient means for manually operating both the latch itself and the auxiliary latch-holding device.

Having thus described the invention, what is claimed is- 1. In a latching device for a cowl, a latch bar pivoted to the cowl to swing in an arc across a face of the cow], said cowl having an elongated arcuate guide concentric with the pivot of the latch bar and also having locking recess adjacent to but spaced from the said arcuate guide,

' and a detent element carried by said latch bar and movable longitudinally thereof for engagement selectively in either the arcuate guide or the locking recess, said detent being of a size to fit snugly in the locking recess to restrain pivotal movement of the latch bar but movable freely along the arcuate guide to permit pivotal movement of the bar within the limits of the guide.

2. In a latching means for a closure, a closure member, a latch member upon the inner face of the closure member and pivotally mounted for rotation in a plane parallel to said inner face, said latch member having a radially elongated slot adjacent one end and a pull-out spring-tensioned stud free to slide and to turn in said slot and having an elliptical section, said closure member having an elongated arcuate slot concentric with the pivot of the latch member and disposed to be in the path of the elliptical section of the stud to receive the same when the stud is positioned in the upper extremity of the slot in the latch member and being of a width substantially equal tothe major axis of the said elliptical cross section, said closure member having also a locking slot of the same size and shape as the elliptical section and positioned to coincide with and to receive the said section when the stud is at-the bottom of the latch member slot in the latching position of the latch member, said locking slot having its major axis at right angles with the center line of the latch member, said closure member being further provided with a connecting slot between the arcuate slot and the locking slot permitting passage of the elliptical stud section from one slot to the other, said connecting slot being of a width substantially equal to the minor axis of the elliptical stud section. a

3. In a latching device, a member having a pair of laterally spaced slots one of which is considerably longer than the other, a latch lever mounted on said member for movement in a plane parallel to the member and into a position in which a portion of the lever bridges the slots, said lever having its slot-bridging portion provided with a narrow slot elongated in a direction substantially transversely of said slots, a stud extending through said narrow slot and having a buttonlike piece thereon, said stud being movable longitudinally of the narrow slot for disposing the button-like piece opposite either one of the laterally spaced slots and being movable transversely through the narrow slot for moving the said piece in or out of the selected slot, elastic stud tensioning means normally operating to draw the stud in a direction tending to maintain the button-like piece within the selected slot, and an operatingknob on said stud for moving the same against the resistance of the stud-tensioning means.

LA VERGNE COOK. 

